An Optimization Method for the Shaping of the Reverse Turbine Rotor Blades

Abstract

The object of the present invention is to provide an optimized shaping method for the reverse-rotation turbine moving blades, which includes the following steps: According to the aerodynamic parameters of the reverse-rotation turbine, give the shaping parameters of the reverse-rotation turbine moving blades; complete the blade shaping of the reverse-rotation turbine moving blades; obtain the aerodynamic performance parameters of the reverse-rotation turbine; carry out the calculation of the blowing loss under the reverse-rotation state of the reverse-rotation turbine moving blades to obtain the reverse-rotation blowing loss of the reverse-rotation turbine; reduce the chord length of the moving blade or increase the installation angle of the moving blade, and at the same time increase the geometric angle at the outlet of the moving blade, and reconstruct the profile lines of the pressure side and the suction side of the mid-section of the reverse-rotation turbine moving blade; construct a three-dimensional model of the reverse-rotation turbine moving blade; obtain the aerodynamic performance parameters of the reverse-rotation turbine after adjusting the blade profile; carry out the calculation of the blowing loss under the reverse-rotation state of the reverse-rotation turbine moving blades to obtain the reverse-rotation blowing loss of the reverse-rotation turbine after adjusting the blade profile. The present invention can not only meet the requirements of the aerodynamic performance parameters of the reverse-rotation turbine, but also minimize the blowing loss of the reverse-rotation turbine moving blades during reverse operation to the greatest extent.

Description

Technical Field

[0001] The present invention relates to a gas turbine modeling method, specifically a reverse turbine modeling method. Background Art

[0002] Since its birth, gas turbines have been favored by various countries due to their high power density and rapid response. Gas turbines have become the main power source for medium and large-sized surface ships.

[0003] Currently, the reverse function of marine gas turbines is mainly achieved through controllable pitch propellers. The emergence of reverse turbines provides a new way for gas turbine reverse, that is, the gas turbine has the ability to rotate forward and backward, and the forward and reverse powers are directly provided by the gas turbine.

[0004] The reverse function of the gas turbine is realized by a reverse turbine with the ability to rotate forward and backward. The moving blades of this turbine are composed of double-layer blades. Usually, the inner-layer blades are forward turbine blades, and the outer-layer blades are reverse turbine blades. The two layers of blades are integrated and connected to the shaft through the turbine disk to output power. When all the gas flow passes through the inner-layer blades, the forward turbine blades work, and at this time, the reverse turbine blades rotate in reverse; when all the gas flow passes through the outer-layer blades, the reverse turbine blades work, and at this time, the forward turbine blades rotate in reverse.

[0005] Traditional turbine blade modeling methods focus on blade modeling design from the perspective of how to reduce blade profile losses and improve turbine performance to meet the requirements of performance indicators such as turbine efficiency, but pay insufficient attention to the blade modeling design method of reverse turbine moving blades. Researchers urgently hope for an advanced blade optimization modeling method that can meet the special working requirements of marine reverse turbines to avoid the problem of excessive blowing loss caused by ignoring the long-term reverse state while pursuing performance under normal working conditions. Summary of the Invention

[0006] The purpose of the present invention is to provide an optimized modeling method for reverse turbine moving blades that can solve the problems such as excessive blowing loss caused by ignoring the long-term reverse state during the design of reverse turbine blades of marine reversible gas turbines.

[0007] The purpose of the present invention is achieved as follows:

[0008] An optimized modeling method for reverse turbine moving blades of the present invention is characterized in that:

[0009] (1) According to the aerodynamic parameters of the reverse turbine, give the modeling parameters of the reverse turbine moving blades: the number of blades, the axial chord length, the chord length or installation angle, the leading edge radius, the trailing edge radius, the inlet geometric angle, the outlet geometric angle, the front wedge angle, the tail wedge angle, the maximum thickness, the stagger angle;

[0010] (2) Adopt the traditional turbine modeling method and use Bezier curves Construct the pressure side and suction side profiles of the mid-section of the reverse turbine rotor blade for 0 ≤ t ≤ 1. Use the extrusion function of 3D modeling software to construct the 3D model of the reverse turbine rotor blade, and complete the shaping of the reverse turbine rotor blade.

[0011] (3) Use a full 3D numerical simulation software to perform a full 3D flow field calculation and analysis of the reverse turbine stage for the reverse turbine rotor blade obtained by the traditional turbine blade shaping method and the reverse turbine stator blade, and obtain the aerodynamic performance parameters of the reverse turbine.

[0012] (4) Based on the reverse turbine blade obtained in step (2), use a full 3D numerical simulation software to carry out the calculation of the blower loss in the reverse state of the reverse turbine rotor blade, obtain the reverse blower loss of the reverse turbine, record this value as the basis for subsequent comparison.

[0013] (5) Based on the blade profile shaping parameters of the reverse turbine rotor blade given in step (1), without changing the flow passage size and the parameters used for blade manufacturing: the number of blades, axial chord length, leading edge radius, trailing edge radius, inlet geometric angle, front wedge angle, trailing wedge angle, reduce the chord length of the rotor blade or increase the installation angle of the rotor blade, and at the same time increase the outlet geometric angle of the rotor blade. Use Bezier curves Re-construct the pressure side and suction side profiles of the mid-section of the reverse turbine rotor blade for 0 ≤ t ≤ 1.

[0014] (6) Based on the adjusted reverse turbine rotor blade profile in step (5), use the extrusion function of 3D modeling software to construct the 3D model of the reverse turbine rotor blade.

[0015] (7) Use a full 3D numerical simulation software to perform a full 3D flow field calculation and analysis of the reverse turbine stage for the 3D model of the reverse turbine rotor blade obtained in step (6) and the reverse turbine stator blade, and obtain the aerodynamic performance parameters of the reverse turbine after adjusting the blade profile.

[0016] (8) Based on the reverse turbine blade obtained in step (5), use a full 3D numerical simulation software to carry out the calculation of the blower loss in the reverse state of the reverse turbine rotor blade, and obtain the reverse blower loss of the reverse turbine after adjusting the blade profile.

[0017] The present invention may further include:

[0018] 1. If the power and efficiency aerodynamic performance parameters of the reverse turbine stage obtained in step (3) meet the predetermined standards, then proceed to the next step; if they do not meet the predetermined standards, then repeat steps (1) to (3) until the aerodynamic performance parameters of the reverse turbine stage reach the predetermined standards.

[0019] 2. If the adjusted aerodynamic performance parameters of the reverse turbine stage, such as power and efficiency, obtained in step (7) meet the predetermined standards, then proceed to the next step; if they do not meet the predetermined standards, repeat steps (5) to (7) until the aerodynamic performance parameters of the reverse turbine stage reach the predetermined standards.

[0020] 3. If the adjusted reverse turbine reverse blowing loss obtained in step (8) meets the predetermined standards, then the optimization of the reverse turbine moving blade profile is completed; if it does not meet the predetermined standards, repeat steps (5) to (8) until the reverse turbine reverse blowing loss reaches the predetermined standards.

[0021] 4. The reverse turbine moving blade is a straight blade, that is, the blade profile of the root section and the top section of the reverse turbine moving blade is the same, and the blade is obtained by stretching the profile line of one section.

[0022] The advantages of the present invention are as follows:

[0023] 1. Based on the full utilization of the traditional gas turbine turbine blade modeling and aerodynamic analysis methods and meeting the performance index requirements of the reverse turbine, by optimizing and adjusting individual parameters of the reverse turbine moving blade profile, the reverse turbine reverse blowing loss is reduced to the greatest extent. Compared with the traditional modeling method that only considers the aerodynamic performance under the working state of the reverse turbine, the optimization design method of the present invention can reduce the blowing loss by more than 20% when the reverse turbine is in the reverse state for a long time, improve the efficiency when the reversible turbine operates normally (the forward turbine operates in the forward state and the reverse turbine operates in the reverse state), is beneficial to reducing the energy consumption of the reversible turbine, and improving the endurance of the ship.

[0024] 2. The optimization modeling method of the reverse turbine moving blade proposed by the present invention, aiming at the blowing loss in the reverse state of the reverse turbine, combines the existing engineering experience, and focuses on optimizing and adjusting the moving blade profile parameters, which can effectively control the blowing loss of the marine reversible gas turbine reverse turbine, and is beneficial to improving the performance of the marine reversible gas turbine during the forward operation.

[0025] 3. The optimization modeling method of the reverse turbine moving blade proposed by the present invention has a shorter chord length of the reverse turbine moving blade and a lighter mass of the reverse turbine moving blade, which is beneficial to improving the stress state of the moving blade and increasing the service life of the reversible turbine moving blade. Brief Description of the Drawings

[0026] Figure 1 is a flow chart of the present invention;

[0027] Figure 2 is a schematic diagram of the reverse turbine moving blade profile parameters;

[0028] Figure 3 is a schematic diagram of the reverse turbine moving blade profile designed by the conventional turbine blade modeling method;

[0029] Figure 4 Schematic diagram of the moving blade of a reverse turbine designed by a conventional turbine blade modeling method;

[0030] Figure 5 Schematic diagram of the profile line of the moving blade of a reverse turbine designed by using the present invention;

[0031] Figure 6 Schematic diagram of the moving blade of a reverse turbine designed by using the present invention;

[0032] Figure 7 Comparison diagram of the profile line of the moving blade of a reverse turbine designed by using the present invention and the profile line of the moving blade of a reverse turbine designed by a conventional turbine blade modeling method. Detailed implementation manners

[0033] The present invention will be described in more detail with reference to the accompanying drawings as follows:

[0034] Combined with Figures 1-7 , detailed implementation manner 1: The implementation steps of an optimization modeling method for the moving blade of a reverse turbine in this implementation manner are as Figure 1 shown, and the specific process is as follows:

[0035] Step 1: According to the aerodynamic parameters of the reverse turbine, give the modeling parameters of the moving blade of the reverse turbine (as Figure 2 shown): number of blades, axial chord length, chord length (or installation angle), leading edge radius, trailing edge radius, inlet geometric angle, outlet geometric angle, front wedge angle, trailing wedge angle, maximum thickness, stagger angle;

[0036] Step 2: Adopt the traditional turbine modeling method, and use Bezier curves 0≤t≤1) to construct the profile lines of the pressure side and the suction side of the mid-section of the moving blade of the reverse turbine (as Figure 3 shown), and construct the three-dimensional model of the moving blade of the reverse turbine through the stretching function of the three-dimensional modeling software (as Figure 4 shown) to complete the modeling of the moving blade of the reverse turbine;

[0037] Step 3: Use the full three-dimensional numerical simulation software to perform a full three-dimensional flow field calculation and analysis of the reverse turbine stage for the moving blade of the reverse turbine obtained by the traditional turbine blade modeling method and the guide vane blade of the reverse turbine to obtain the aerodynamic performance parameters of the reverse turbine;

[0038] If the aerodynamic performance parameters such as the power and efficiency of the reverse turbine stage obtained in Step 3 meet the predetermined standards, then proceed to the next step; if they do not meet the predetermined standards, then repeat Steps 1 to 3 until the aerodynamic performance parameters of the reverse turbine stage reach the predetermined standards;

[0039] Step 4: Based on the reverse turbine blades obtained in Step 2, use a full three-dimensional numerical simulation software to carry out the calculation of the blowing loss under the reverse rotation state of the moving blades of the reverse turbine, obtain the reverse blowing loss of the reverse turbine, record this value, and use it as the basis for subsequent comparison;

[0040] Step 5: Based on the blade profile modeling parameters of the moving blades of the reverse turbine given in Step 1, without changing the flow-through dimensions and the parameters used for the blades: the number of blades, the axial chord length, the leading edge radius, the trailing edge radius, the inlet geometric angle, the front wedge angle, and the trailing wedge angle, reduce the chord length of the moving blade or increase the installation angle of the moving blade, and at the same time increase the outlet geometric angle of the moving blade, and use a Bessel curve 0≤t≤1) to reconstruct the pressure side and suction side profiles of the mid-section of the moving blades of the reverse turbine (as Figure 5 shown);

[0041] Step 6: Based on the profile of the moving blades of the reverse turbine adjusted in Step 5 (as Figure 5 shown), use the stretching function of the three-dimensional modeling software to construct a three-dimensional model of the moving blades of the reverse turbine (as Figure 6 shown);

[0042] Step 7: Use the full three-dimensional numerical simulation software to perform a full three-dimensional flow field calculation and analysis of the reverse turbine stage on the three-dimensional model of the moving blades of the reverse turbine obtained in Step 6 (as Figure 6 shown) and the guide blades of the reverse turbine to obtain the aerodynamic performance parameters of the reverse turbine after adjusting the blade profile;

[0043] If the aerodynamic performance parameters such as the power and efficiency of the reverse turbine stage obtained in Step 7 meet the predetermined standards, then proceed to the next step; if they do not meet the predetermined standards, then repeat Steps 5 to 7 until the aerodynamic performance parameters of the reverse turbine stage reach the predetermined standards;

[0044] Step 8: Based on the reverse turbine blades obtained in Step 5, use a full three-dimensional numerical simulation software to carry out the calculation of the blowing loss under the reverse rotation state of the moving blades of the reverse turbine, obtain the reverse blowing loss of the reverse turbine after adjusting the blade profile, and compare it with the blowing loss when the blade profile was not adjusted in Step 4;

[0045] If the reverse blowing loss of the reverse turbine obtained in Step 8 meets the predetermined standards, then the optimization of the blade profile of the moving blades of the reverse turbine is completed; if it does not meet the predetermined standards, then repeat Steps 5 to 8 until the reverse blowing loss of the reverse turbine reaches the predetermined standards.

[0046] Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that the moving blades of the reverse turbine are straight blades, that is, the blade profiles of the root section and the top section of the moving blades of the reverse turbine are the same, and the blades are obtained by stretching the profile of one section.

[0047] Other steps and parameters are the same as those in the first specific embodiment.

[0048] Specific Embodiment 3: The difference between this embodiment and one of the first to second specific embodiments is that the installed angle and outlet geometric angle of the moving blades of the reverse turbine after optimization and adjustment are relatively large (as Figure 7 shown), which can reduce the blowing loss by more than 20% when the reverse turbine is in the reverse state for a long time, improve the efficiency when the reversible turbine operates normally (the forward turbine operates in the forward state and the reverse turbine operates in reverse), is conducive to reducing the energy consumption of the reversible turbine, and improving the endurance of the ship.

[0049] Other steps and parameters are the same as those in one of the first to second specific embodiments.

[0050] Specific Embodiment 4: The difference between this embodiment and one of the first to third specific embodiments is that the chord length of the moving blades of the reverse turbine after optimization and adjustment is relatively short (as Figure 7 shown), and the mass of the moving blades of the reverse turbine is relatively light, which is conducive to improving the stress state of the moving blades and increasing the service life of the moving blades of the reversible turbine.

[0051] Other steps and parameters are the same as those in one of the first to third specific embodiments.

[0052] Specific Embodiment 5: The difference between this embodiment and one of the first to fourth specific embodiments is that the full three-dimensional numerical simulation software is NUMECA and CFX software.

[0053] Other steps and parameters are the same as those in one of the first to fourth specific embodiments.

[0054] Specific Embodiment 6: The difference between this embodiment and one of the first to fifth specific embodiments is that the three-dimensional modeling software is UG software.

[0055] Other steps and parameters are the same as those in one of the first to fifth specific embodiments.

[0056] In summary, the present invention relates to a method for optimizing the shape of the moving blades of a reverse turbine that can meet the requirements of the aerodynamic performance parameters of the reverse turbine and can minimize the blowing loss when the moving blades of the reverse turbine operate in reverse to the greatest extent, and uses a Bessel curve. The purpose of the present invention is to solve the problem that the blowing loss is relatively large due to the neglect of the long-term reverse state of the reverse turbine blades during the design of the reverse turbine of a marine reversible gas turbine, and then provides a method for optimizing the shape of the moving blades suitable for the reverse turbine of a marine reversible gas turbine. The present invention is used to improve the field of optimizing the moving blades of the reverse turbine of a marine reversible gas turbine.

Claims

1. An optimized shaping method for the moving blades of a reverse turbine, characterized in that: (1)According to the aerodynamic parameters of the reverse turbine, give the shaping parameters of the reverse turbine rotor blades: the number of blades, the axial chord length, the chord length or the installation angle, the leading edge radius, the trailing edge radius, the inlet geometric angle, the outlet geometric angle, the front wedge angle, the trailing wedge angle, the maximum thickness, and the stagger angle; (2) Using the traditional turbine modeling method, with Bezier curves Construct the pressure side and suction side profiles of the mid-section of the reverse turbine moving blade, and build the three-dimensional model of the reverse turbine moving blade through the stretching function of the three-dimensional modeling software to complete the modeling of the reverse turbine moving blade; (3)Use a full three-dimensional numerical simulation software to perform a full three-dimensional flow field calculation and analysis of the reverse turbine stage for the reverse turbine rotor blades obtained by using the traditional turbine blade shaping method and the reverse turbine stator blades to obtain the aerodynamic performance parameters of the reverse turbine; (4)Based on the reverse turbine blades obtained in step (2), use a full three-dimensional numerical simulation software to carry out the calculation of the blowing loss in the reverse rotation state of the reverse turbine rotor blades, obtain the reverse rotation blowing loss of the reverse turbine, record this value as the basis for subsequent comparison; (5) Based on the blade profile modeling parameters of the reverse turbine rotor blades given in step (1), without changing the flow passage size and the parameters used for blade manufacturing: the number of blades, axial chord length, leading edge radius, trailing edge radius, inlet geometric angle, front wedge angle, trailing wedge angle, reduce the chord length of the rotor blades or increase the installation angle of the rotor blades, and at the same time increase the outlet geometric angle of the rotor blades, and use Bezier curves Reconstruct the pressure side and suction side profiles of the mid-section of the reverse turbine rotor blades; (6)Based on the reverse turbine rotor blade profile adjusted in step (5), construct a three-dimensional model of the reverse turbine rotor blade through the stretching function of the three-dimensional modeling software; (7)Use a full three-dimensional numerical simulation software to perform a full three-dimensional flow field calculation and analysis of the reverse turbine stage for the three-dimensional model of the reverse turbine rotor blade obtained in step (6) and the reverse turbine stator blades to obtain the aerodynamic performance parameters of the reverse turbine after adjusting the blade profile; (8)Based on the reverse turbine blades obtained in step (6), use a full three-dimensional numerical simulation software to carry out the calculation of the blowing loss in the reverse rotation state of the reverse turbine rotor blades, and obtain the reverse rotation blowing loss of the reverse turbine after adjusting the blade profile.

2. The optimized shaping method for the moving blades of a reverse turbine according to claim 1, characterized in that: If the power and efficiency aerodynamic performance parameters of the reverse turbine stage obtained in step (3) meet the predetermined standards, then perform the next step; if they do not meet the predetermined standards, then repeat steps (1) to (3) until the aerodynamic performance parameters of the reverse turbine stage reach the predetermined standards.

3. The optimized shaping method for the moving blades of a reverse turbine according to claim 1, characterized in that: If the power and efficiency aerodynamic performance parameters of the reverse turbine stage obtained after adjustment in step (7) meet the predetermined standards, then perform the next step; if they do not meet the predetermined standards, then repeat steps (5) to (7) until the aerodynamic performance parameters of the reverse turbine stage reach the predetermined standards.

4. The optimized shaping method for the moving blades of a reverse turbine according to claim 1, characterized in that: If the reverse rotation blowing loss of the reverse turbine obtained after adjustment in step (8) meets the predetermined standards, then the optimization of the reverse turbine rotor blade profile ends; if it does not meet the predetermined standards, then repeat steps (5) to (8) until the reverse rotation blowing loss of the reverse turbine reaches the predetermined standards.

5. The optimized shaping method for the moving blades of a reverse turbine according to claim 1, characterized in that: The reverse turbine rotor blades are straight blades, that is, the blade profiles of the root section and the tip section of the reverse turbine rotor blades are the same, and the blades are obtained by stretching the profile of one section.

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